Purchasing a bike online is becoming increasingly popular, with fewer bikes bought in-store every day.

This, however, makes choosing your bike size increasingly important as you cannot try bikes for size as you can in store.

This article will breakdown everything you need to know about bike size chart, then you can choose the perfect sized bike to spin your 2019 in the right direction.

Bike size chart guide infographic 2019

Here are details insight from our bike size chart infographic.

1. What is my bike size?

Finding your ideal bike size is essential to both the comfort and enjoyment of your new bike. A bike too small or too big will place extra stress on your body in places such as your knees and back, increasing the likelihood of injury.

It is important to note that different kinds of bikes also have different sizing, a mountain bike won’t fit the same size as a road bike and a BMX won’t fit the same size as a mountain bike. It is therefore essential to do your research and look up the specific sizing of the bike you are after, read reviews, use size-charts and ask questions on online forums/live-chats if possible. The more information you have the better.

If buying a bike in-store, trying the bike before you buy is the obvious option. This will allow you to see if it is the right fit if it is comfortable and if you actually like the bike and can see yourself riding it. Buying in-store often means you can invest in a professional bike-fit, allowing for your sizing and dimensions to be measured up whilst being walked through the entire process.

2.How to measure bike frame size

Measuring a classic road bike frame size is a relatively simple task. To measure:

bike frame size

1) Find the top of the seat tube (this is where the seat post is held)

2) Find the center of the bottom bracket (This holds the crank arms together)

3) Measure the distance between these 2 points

4) Record this in both cm and inch to find the right frame for you

As you can see on our bike geometry, the ST is the frame size.

How to measure adult bike size

Adult bike size is measured on both height and inseam size. Inseam size is often regarded as more accurate measurement, however, it is useful to measure both and compare to receive the best fitting bike. A guide on how to measure both height and inseam length will be covered later in this post.

How to measure children bike size

Ensuring the right bike size for a child is essential. Not only does it provide comfort, but it also improves the safety of the bike itself. How exactly do you measure a children’s bike size you ask? 

If possible, it is recommended to bring them into a local store and simply let them try out a variety of different bikes. This will allow them to get a feel for what is right, comfortable and safe. With hands-on experts, the process is a lot easier, allowing the safety of your child to be put first.

If however, purchasing a bike online, it is recommended to measure the height of your child beforehand. Unlike adult bike sizing done by frame, children’s bike size is done based on wheel diameter. 

This, therefore, means measuring the height of the child and matching it to the correct wheel diameter to ensure a perfect and safe fit, allowing you to rest easy. Be sure to invest in a quality helmet to go with the new bike, with an extensive range available you will be certain to find one which appeals to them.

3. What bike frame size do I need?

Picking the right bike frame size is ultimately down to personal preference. With different kinds of bikes hosting different riding styles it is important to determine what kind of bike you are looking to purchase. Whether buying for a child or adult, there are various ways to measure bike-size without the need to go in store, these will be covered below.

What kind of bike do you ride?

Depending on the kind of bike you ride or want to ride, will determine your size along with your riding style.

For example, mountain biking is a lot more aggressive than road biking and may require a smaller sized bike to make it more maneuverable through different terrains and obstacles, whereas a cross-country racing bike may be sized slightly larger to allow more speed to be generated.

Bike size, however, is simply personal preference, what works for you most likely won’t work for others, therefore, it is essential to size yourself up and try different kinds of bikes before buying.

Bike frame size for height

Measuring bike frame size by height could never be easier. 

Simply stand up straight against a wall, shoes off, legs together, shoulders back whilst somebody marks with a pencil the top of your head. 

Your height is used to match bike frame size along with inseam size. Inseam size is often regarded as a more accurate approach, however, it doesn’t hurt to measure both increasing the accuracy of your bike fit. Inseam size will be discussed below.

What is inseam size?

Inseam size is often regarded as one of the most important factors when choosing a frame size. Inseam is simply the measurement from the floor to the highest possible crotch position measured in cm.

How to measure the inseam

Measuring the inseam can be done relatively easily, requiring only 2 people and a book only taking a fraction of time. To begin:

  1. Stand with your back against the wall and feet positioned 6-8 inches apart
  2. Place a book between your legs, spine-up, raise until the book mimics a bike seat and is positioned between your legs
  3. Get a second person to measure from the top-of-the book to the floor (cm) this is your inseam length

Alternatively, if visiting a store and receiving a professional bike-fit this will be done for you. This is recommended if you do not feel comfortable measuring the inseam or your bike fit size yourself.

4. Bike size chart

Below is a list of different bike size charts depending on the type of bike you are looking to purchase. It is important to use the correct chart based on bike type and gender to ensure the perfect fit. Alternatively, skip ahead and use the bike size calculator to find the right size and type of bike for you.

Women’s bike sizes chart

Due to women generally having shorter upper bodies than men along with shorter top-tubes on bikes, women’s bikes are made slightly different. It is important to check to size against women’s charts unless the bikes are unisex such as triathlon bicycles. This will ensure a comfortable and optimal fit to enhance your cycling experience.

Road bike size chart (Women)

women road bike size chart
Height (cm)Road bike size (cm)
148 – 152 cm44 cm (XX small)
152 – 160 cm48 cm (X small)
160 – 168 cm51 cm (small)
168-175 cm54 cm (medium)

Mountain bike size chart (Women)

women's mountain bike size chart
Height (cm)Mountain bike size (inch)
148 – 158 cm13 – 14”
158 – 168 cm15 – 16”
168 – 178 cm17 – 18”
178 – 185 cm19” +

Road bike size chart (Men)

men's road bike size chart
Inside-leg (cm)Height (cm)Road Bike Size (cm)
71 -75 cm152 – 160 cm48 cm (XX small)
75 – 79 cm160 – 170 cm51 cm (small)
79 – 83 cm170 – 174 cm54 cm (medium)
83 – 85 cm174 – 180 cm56 cm (large)
85 – 89 cm180 – 188 cm57 cm (X-large)
89 – 92 cm188 – 195 cm60 cm (XX large)
92 + cm195 + cm63 cm (XXX large)

Mountain bike size chart (Men)

men's mountain bike size chart
Inside-leg (cm)Height (cm)Mountain bike size (inches)
71 -75 cm152 – 160 cm15” (X-small)
75 – 79 cm160 – 170 cm16” (small)
79 – 83 cm170 – 174 cm17” (medium)
83 – 85 cm174 – 180 cm18” (medium)
85 – 89 cm180 – 188 cm19” (large)
89 – 92 cm188 – 195 cm20” (large)
92 + cm195 + cm21” (X-large)

Triathlon bike size chart (Women & Men )

triathlon bike size chart (men & women)
Height (cm)Inside leg (inch)Frame size (cm)Top tube length (cm)
152.5 – 160cm26.5 – 28”48 – 50 cm48.5 – 50 cm
157.5 – 165 cm27.5 – 29”50 – 52 cm50 – 51.5 cm
162.5 – 170 cm28.5 – 30”52 – 54 cm51.5 – 53.5 cm
167.5 – 175 cm29.5 – 31”54 – 56 cm53.5 – 55.5 cm
172.5 – 180 cm30.5 – 32”56 – 58 cm55.5 – 57 cm
177.5 – 185 cm31.5 – 33”58 – 60 cm57 – 58 cm
182.5 – 190 cm32.5 – 34”60 – 62 cm58 – 59 cm

Bike size chart for kids

bike size chart for kid
Age (years)Height (cm)Wheel diameter (inch)
2 – 585 – 110 cm12
2 – 485 – 100 cm14
3 – 595 – 110 cm16
5 -7110 – 120 cm20
7 – 9120 – 135 cm22
9 – 11135 – 145 cm24
11 +145 + cm26

BMX bike size chart

bmx bike size chart
Age (years)Height (cm)Wheel size (inch)
5-7110 – 122 cm16”
7 – 11122 – 147 cm18”
11 +147 – 193 cm20”

Fixie/single-speed bike size chart

fixie (single speed) bike size chart
Height (inch)Inside leg (inch)Frame size (cm)
5’1” – 5’3”27 – 29”48 cm
5’3” – 5’5”28 – 30”50 cm
5’5” – 5’7”29 – 31”52 cm
5’7” – 5’9”30 – 32”54 cm
5’9” – 5’11”31 – 33”56 cm
5’11” – 6’2”32 – 34”58 cm
6’1” – 6’5”33 – 35”60 cm

Men’s hybrid/ city bike sizing chart

men's hybrid (city) bike sizing chart
Height (cm)Frame size (cm)Hybrid frame size
148 – 158 cm33 – 37 cmX-Small
158 – 168 cm38 – 42 cmSmall
168 – 178 cm43 – 47 cmMedium
178 – 185 cm48 – 52 cmLarge
185 – 193 cm53 – 57 cmX-Large
193 – 198 cm58 – 61 cmXX-Large

Women’s hybrid/ city bike sizing chart

women's hybrid (city) bike sizing chart
Height (cm)Frame size (inch)Hybrid frame size
148 – 158 cm13 – 14”X-Small
158 – 168 cm15 – 16”Small
168 – 178 cm17 – 18”Medium
178 – 185 cm19” +Large

5. Bike Size Calculator

If you are still confused about what bike size should you choose. Personally we use the frame size calculator from Ebicycles’ online calculator 

First, choose the bicycle type you want to ride. Here we choose “Road Bike”

Choose a bike type

Second, input your personal information. Here we input “Adult, male”, “175cm” “80cm leg length”.

Rider Information

Vola! You will get a detailed report for the bike size you need, includes frame size (in centimeters and inches) and crank size. Easy, right?

Bike size calculator result

6. Bike Fitting Guide

If you are riding a road bike or mountain bike for racing purpose, then it’s better to get a bike fitting before you finally ride on the bike.


Cause you want to know your perfect body position on the bike for highest efficient riding. 

1) Amazon Bike Fit Guide

In Amazon bike fit guide, you can see they are listing “Adult road bike sizing chart”, “Adult mountain bike sizing chart” and “Kids’ bike sizing chart”. More details check their website.

Amazon Bike Fit Guide

2) Jenson USA Bike Fit Calculator (Beta)

This bike fit calculator is quite professional. Based on their requirements, you’d better prepare these infos before get ready to calculate your fitting data.

For example, Foot length, arm length, inseam length and so on.

More details check their calculator here.

Jenson USA Bike Fit Calculator ​

3) Check your local bike shop with bike fitting services.

Search online and find the bike shops who can offer bike fitting services, then go and find your perfect fitting date.